1. Field of the Invention
The present invention relates to an anti-lock brake structure, particularly to a brake assembly having a slidable holder slidably receiving a brake base and connected to a brake shoe. Two wheel sets and two anti-lock inclined surfaces are disposed between the brake base and the slidable holder. An elastomer is received in a seat member which is connected to the slidable holder. When braking, the slidable holder relative to the brake base by an inertial force of a wheel rim and a biasing force of the elastomer. Each wheel set rolls and reciprocates between the shallow section and the deeper section of the corresponding anti-lock inclined surface of the slidable holder. The brake shoe is tightly or loosely rubbed against the wheel rim to provide an anti-lock brake effect.
2. Description of Related Art
Applicant has applied several Taiwan patents which includes Taiwan Patent Certification No. 241967, 261564, and 229046 all disclose an anti-lock brake structure. Taiwan Patent Application No. 96101658 and 96101659 disclose a positioning structure of an elastomer for an anti-lock brake structure. However, the five references cited above have some disadvantages which are as follows:
First, the cited references all disclose that at least one rollable member movably abuts against at least one anti-lock inclined surface, such that an anti-lock brake effect is provided. But when a braking force is increased, a friction force between the at least one rollable member and the at least one anti-lock inclined surface is enlarged. And the operation of the braking structure would become insensitive and slow.
Second, a slidable holder disclosed by the cited references is slidably received in a brake base. A brake shoe is disposed within the slidable holder. The brake shoe and a support member are integrally molded for being waterproof and dustproof. A dust cover sleeves on the support member and the brake base. But it is necessary to have an operational space between the support member and the brake base and an operational space between the dust cover and the brake base. The brake base has a space for receiving an elastomer. Therefore, the brake base and the slidable holder are designed to have a larger size.
Third, the slilable holder which is disclosed by the cited references moves along a curved groove defined in the brake base. Due to a curved movement of the slidable holder, a positioning shaft which is used to press the elastomer would have a large displacement relative to an abutting surface of the slidable holder.
The present invention has arisen to mitigate and/or obviate the disadvantages of the conventional anti-lock brake structure.